canton of Montmartin-sur-Mer (canton de Montmartin-sur-Mer)
- canton of France
- Country:
- Capital: Montmartin-sur-Mer
- Coordinates: 48° 59' 1" N, 1° 29' 45" E
- GPS tracks (wikiloc): [Link]
- Wikidata storage: Wikidata: Q1726344
- INSEE canton code: [5023]
Includes regions:
Trelly
- commune in Manche, France
- Country:
- Postal Code: 50660
- Coordinates: 48° 57' 36" N, 1° 25' 35" E
- GPS tracks (wikiloc): [Link]
- Area: 11.77 sq km
- Population: 662